The present disclosure relates to the field of displaying technology, in particular to a Polysilicon Thin-Film Transistor (P-Si TFT) and a method for fabricating the same, an array substrate and a method for fabricating the same, and a display device.
As compared with amorphous silicon (a-Si) array substrates, low-temperature Polysilicon (P-Si) array substrates is characterized in advantages such as high mobility (even several hundred times as high as that of a-Si). Accordingly, Thin-Film Transistors (TFTs) on a P-Si array substrate can be made very small in size and have a fast response. Today, such a P-Si array substrate is a prevailing array substrate for a display panel, and has been widely applied in the field of Organic Light Emitting Display (OLED) panel and Liquid Crystal Display (LCD) panel for having both high resolution and good displaying quality.
However, a low-temperature Polysilicon Thin-Film Transistor (P-Si TFT) is of a complex composition and needs more fabricating processes than other kinds of TFTs. As a result, it is time-consuming and cost-consuming for design and mass production of P-Si TFTs. It is also challenging to monitor and is inferior in terms of stability. For example, as shown in FIG. 1, with respect to such a storage capacitor structure of the low-temperature P-Si array substrate formed by two layers of gate electrode metal in related arts, it is quite vulnerable in terms of high leakage electricity and poor reliability. As shown in FIG. 1, reference numeral 1 represents a base substrate, reference numeral 2 represents an active layer, reference numeral 3 represents a first gate insulation layer, reference numeral 4 represents a first gate electrode, reference numeral 5 represents a second gate insulation layer, reference numeral 6 represents a storage capacitor bottom electrode, and reference numeral 7 represents a storage capacitor top electrode. It is clear that these components illustrated by reference numerals 1˜7 constitute a P-Si TFT on the left and a storage capacitor on the right as shown in FIG. 1.